BioaccumulationBioaccumulationBiomagnificationBiomagnification

Neda Valcheva Alex Popov

Elizabeth Karlova10/6

BioaccumulationBioaccumulation [1][1]

• the accumulation of a substance in a biological tissue

• up-take and retention via any route• a necessary process for organisms’ survival• considered to be of concern when

substances are present at harmful levels• bioaccumulation factor (BAF)

– the ratio – in a steady state situation – of the concentration of the chemical inside an organism to the concentration in its food

[4]

BioconcentrationBioconcentration[1]

• occurs when an organism takes up and concentrates a chemical directly from the surrounding environment

• bioconcentration factor (BCF)– the ratio of the chemical’s concentration in an organism

compared to the surrounding water [5]

BioaccumulationBioaccumulationvs.vs.

BioconcentrationBioconcentration[1[1]

• Bioconcentration & bioaccumulation– Its physical and chemical properties, including solubility in water

and in fat, molecular weight, and ease of metabolism or degradation

– Environmental conditions, including water quality– The nature of the organism, including its ability to metabolise the

chemical and its fat (lipid) content

• Bioaccumulation– Dietary factors– How readily the organism absorbs the chemical from its food

BiomagnificationBiomagnification[1]

• accumulation and transfer of substances via the food web, with an increase of concentrations in organisms at successive trophic levels

• biomagnification factor (BMF)– the ratio of the concentration of a

substance in the predator compared with the prey

[6]

PollutantsPollutants[3]

• Organochlorines• Polychlorinated biphenyls (PCBs) [7]

• Heavy Metals - mercury, cadmium, lead, tin

• Mercury [8]

Case Study #1: Clear LakeCase Study #1: Clear Lake [3][3]

• (in 1949) DDD: Used to kill the midges in the lake

• 1 DDD / 7 million water parts • 99% midges – killed; reappeared overtime • 5 years later: Used more DDD• Killed Western Grebes as a result• 3 years later (1957): The same happened

again• What caused this?

Case Study #1: MAP

Clear lake!

Case Study #2: Britain[3]

• 1960: Decrease in the sparrow hawk population!

• Due to organochlorine pesticides that plagued the birds’ prey

• They began laying eggs with very fragile shells• What really happened???• After that, from 1963 to 1986 the pesticides

were replaced => Increase in the population again!

Case Study #2: MAP

Works Cited1. "Bioaccumulation: Definitions and Implications." Euro Chlor: 1-2. 

     Eurochlor.org. Web. 13 June 2010. <http://www.eurochlor.org/      upload/documents/document52.pdf>

2. "Biomagnification." Monterey Institute for Technology and Education. Monterey      Institute for Technology and Education, 2010. Web. 13 June 2010.      <http://www.montereyinstitute.org/noaa/lesson13/l13la1.html>.

3. Taylor, Brian. "Bioaccumulation and Biomagnification." Bio Factsheet 1997, 14th      ed.: 1-3. Web. 13 June 2010. <http://www.williamhoward.cumbria.sch.uk/      intranet/Science/KS5/Abiology/Factsheets/factsheets172/Bio%20Press%20Fac

tsheets/      14%20bio%20accumulation.pdf>.

IMAGES4. http://www.esd.ornl.gov/BMAP/pics/logo1.JPG5. http://pubs.usgs.gov/fs/fs-031-03/images/fig02b.jpg6. http://web.bryant.edu/~dlm1/sc372/readings/toxicology/biomagnification.jpg7. http://www.umbi.umd.edu/~sowers/images/RecyclePCB.jpg8. http://blog.deborahblum.com/wp-content/uploads/2010/03/mercury_drops_large.jpg9. http://www.mallardhouse.com/images/Map-Regional.jpg10. http://www.neilhair.com/wp-content/uploads/0_map_britain_1987_enlarged.jpg